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United States Patent |
5,090,750
|
Lindqvist
|
February 25, 1992
|
Locking mechanism for sash type windows
Abstract
A locking mechanism for windows having upper and lower sashes slidably
disposed in a window frame. In the locked position of the mechanism,
locking bolts mounted on the transverse rail of one sash engage a sidewall
of a guide groove in the window frame, thereby forcing that sash towards
the other sash to effect a better seal between the sashes. Optionally, at
least one sash clamp mounted on a transverse rail of one sash is adapted
to engage a cooperating receiving element affixed to the adjacent
transverse rail of the other sash. In the unlocked position of the
mechanism, the sash clamp disengages the receiving element, and the
locking bolts release contact with the sidewall of the guide groove while
still remaining within the groove. The locking mechanism also has a
release position in which the locking bolts are retracted from the guide
groove to permit the sash to be moved transversely for cleaning.
Inventors:
|
Lindqvist; Per-Olof (Onsala, SE)
|
Assignee:
|
Fixfabriken AB (SE)
|
Appl. No.:
|
637177 |
Filed:
|
January 3, 1991 |
Current U.S. Class: |
292/7; 292/36; 292/DIG.20; 292/DIG.47 |
Intern'l Class: |
E05C 009/00 |
Field of Search: |
292/36,DIG. 47,DIG. 20,7,240,241,DIG. 38
|
References Cited
U.S. Patent Documents
336302 | Feb., 1886 | Dudgeon | 292/36.
|
480148 | Aug., 1892 | Theby | 292/36.
|
1041803 | Oct., 1912 | Kilburn | 292/36.
|
1059999 | Apr., 1913 | James | 292/36.
|
1253810 | Jan., 1919 | Gianninoto | 292/DIG.
|
1393628 | Oct., 1921 | Leichter | 292/DIG.
|
1704946 | Mar., 1929 | Lindgren | 292/36.
|
1901974 | Mar., 1933 | Macy | 292/DIG.
|
2537736 | Jan., 1951 | Carlson | 292/DIG.
|
3811718 | May., 1974 | Bates | 292/DIG.
|
Foreign Patent Documents |
2026594 | Feb., 1980 | GB | 292/DIG.
|
Primary Examiner: Nicholson; Eric K.
Attorney, Agent or Firm: Lerner, David, Littenberg, Krumholz & Mentlik
Claims
What is claimed is:
1. A locking mechanism for a window having a window frame including a guide
groove extending in movement directions, and upper and lower sashes at
least one of which is slidable with respect to said frame in said movement
directions, each of said sashes having a meeting rail, said meeting rails
adapted to lie adjacent one another when said sashes are in a closed
position, said locking mechanism comprising
at least one sash clamp connected to one of said meeting rails,
at least one receiving element corresponding to said at least one sash
clamp connected to the other of said meeting rails,
a locking element disposed at an end of said one of said meeting rails and
adapted in an extended position to lie within said guide groove,
a handle moveable between a locked position, an unlocked position and a
release position, and
an operating mechanism including means for engaging said locking element
with a wall of said guide groove and for engaging said at least one sash
clamp with said at least one receiving element responsive to movement of
said handle from said unlocked position to said locked position, said
operating mechanism also including means for disengaging said locking
element from said wall of said guide groove and for disengaging said at
least one sash clamp from said at least one receiving element responsive
to movement of said handle from said locked position to said unlocked
position, said operating mechanism further including means for retracting
said locking element from within said guide groove responsive to movement
of said handle from said unlocked position to said release position.
2. The locking mechanism as claimed in claim 1, wherein said at least one
sash clamp has a first contacting surface and said at least one receiving
element has a first engagement surface, said first contacting surface and
said first engagement surface being sized and shaped so that, upon
engagement of said at least one sash clamp with said at least one
receiving element, said meeting rails are drawn toward one another in
directions transverse to said movement directions.
3. The locking mechanism as claimed in claim 2, wherein said at least one
sash clamp includes a second contacting surface and said at least one
receiving element includes a second engagement surface, said second
contacting surface and said second engagement surface being sized and
shaped so that, upon engagement of said at least one sash clamp with said
at least one receiving element, said upper sash and said lower sash are
displaced away from one another in opposite movement directions.
4. The locking mechanism as claimed in claim 1, wherein said at least one
sash clamp includes a second contacting surface and said at least one said
receiving element includes a second engagement surface, said second
contacting surface and said second engagement surface being sized and
shaped so that, upon engagement of said at least one sash clamp with said
at least one receiving element, said upper sash and said lower sash are
displaced away from one another in opposite movement directions.
5. The locking mechanism as claimed in claim 1, wherein said operating
mechanism further includes first and second intermediate elements, said
handle being selectively engageable to move either of said intermediate
elements, said operating mechanism including first actuating means for
engaging and disengaging said locking element with said wall of said guide
groove and for engaging and disengaging said at least one sash clamp with
said at least one receiving element responsive to movement of said first
intermediate element, said operating mechanism also including second
actuating means for retracting said locking element from within said guide
groove and for extending said locking element into said guide groove
responsive to movement of said second intermediate element.
6. The locking mechanism as claimed in claim 5, wherein said locking
element is pivotable with respect to said one of said meeting rails, and
wherein said first actuating means includes pivoting means for pivoting
said locking element responsive to movement of said first intermediate
element.
7. The locking mechanism as claimed in claim 6, wherein said first
actuating means includes a connecting rod operatively connecting said at
least one sash clamp with said pivoting means.
8. The locking mechanism as claimed in claim 7, wherein said first
actuating means further includes a sash clamp actuator rod operatively
connecting said first intermediate element with said connecting rod.
9. The locking mechanism as claimed in claim 6, wherein said first
actuating means further includes a sash clamp actuator rod operatively
connecting said first intermediate element with said connecting rod.
10. The locking mechanism as claimed in claim 5, wherein said second
actuating means includes a lock pin actuator rod operatively connecting
said second intermediate element with said locking element.
11. The locking mechanism as claimed in claim 6, wherein said second
actuating means includes a lock pin actuator rod operatively connecting
said second intermediate element with said locking element.
12. The locking mechanism as claimed in claim 11, wherein said locking
element is pivotally mounted to said lock pin actuator rod, and wherein
said second actuating means includes means for extending said lock pin
actuator rod towards said guide groove and for retracting said lock pin
actuator rod away from said guide groove responsive to movement of said
second intermediate element.
13. The locking mechanism as claimed in claim 5, wherein said handle
includes a spindle having a shaped member formed thereon, and wherein said
first intermediate element includes an opening sized and shaped to
matingly receive said shaped member upon the selective engagement of said
handle with said first intermediate element, and wherein said second
intermediate element includes an opening sized and shaped to matingly
receive said shaped member upon the selective engagement of said handle
with said second intermediate element.
14. The locking mechanism as claimed in claim 13, wherein said opening in
said first intermediate element is oriented in a first rotational
direction and said opening in said second intermediate element is oriented
in a second rotational direction, said second rotational direction being
different than said first rotational direction by a predetermined angle
when said handle is in said locked position, and said second rotational
direction being substantially equal to said first rotational direction
when said handle is in said unlocked position.
15. The locking mechanism as claimed in claim 1, wherein rotation of said
handle from said unlocked position to said locked position causes said
locking element to engage said wall of said guide groove, whereby said
sash having said one of said meeting rails can be locked in an open
position.
16. The locking mechanism as claimed in claim 1, wherein said window frame
has a second guide groove, further comprising a second locking element
disposed at another end of said one of said meeting rails and adapted in
an extended position to lie within said second guide groove, and said
operating mechanism including means for engaging and disengaging said
second locking element with a wall of said second guide groove responsive
to movement of said handle between said unlocked position and said locked
position, said operating mechanism also including means for retracting
said second locking element from within said second guide groove and for
extending said second locking element into said second guide groove
responsive to movement of said handle between said unlocked position and
said release position.
17. The locking mechanism as claimed in claim 5, wherein said window frame
has a second guide groove, further comprising a second locking element
disposed at another end of said one of said meeting rails and adapted in
an extended position to lie within said second guide groove, and said
operating mechanism including third actuating means for engaging and
disengaging said second locking element with a wall of said second guide
groove responsive to movement of said first intermediate element, said
operating mechanism also including fourth actuating means for retracting
said second locking element from within said second guide groove and for
extending said second locking element into said second guide groove
responsive to movement of said second intermediate element.
18. The locking mechanism as claimed in claim 17, wherein said second
locking element is pivotable with respect to said one of said meeting
rails, and wherein said third actuating means includes pivoting means for
pivoting said second locking element responsive to movement of said first
intermediate element.
19. The locking mechanism as claimed in claim 18, wherein said fourth
actuating means further includes a second lock pin actuator rod
operatively connecting said second intermediate element with said second
locking element.
20. The locking mechanism as claimed in claim 16, wherein rotation of said
handle from said unlocked position to said locked position causes said
second locking element to engage said wall of said second guide groove,
whereby said sash having said one of said meeting rails can be locked in
an open position.
Description
FIELD OF THE INVENTION
The present invention relates to a locking mechanism for application on a
sash type window having upper and lower sliding sashes, each sash being
enclosed by a frame composed of side rails and transverse rails, the top
and bottom transverse rails of the lower and upper sashes respectively
forming the meeting rail of the respective sash which, when the sashes are
in the closed position, abuts the adjacent rail of the other sash, said
locking mechanism being attached to the top surface of the top transverse
rail of the lower sash and being operable by a handle.
BACKGROUND OF THE INVENTION
Locking mechanisms for sash windows are known in which, in the closed
position, the handle of the locking mechanism engages a receiving element
affixed to the adjacent rail of the other window sash. Whilst such an
arrangement is effective in maintaining the window closed, there is no
provision for securely holding the window in an open position, i.e. if the
lower sash is slid upwards, there is no positive locking means to prevent
the sash sliding back down under the force of gravity.
To overcome this problem, locking mechanisms have been developed in which
engagement bolts arranged at the ends of the transverse sash rail on the
locking mechanism are forced into contact with a region of the frame which
surrounds the sash window assembly, thereby hindering movement of the
lower sash. Such an arrangement has the disadvantages that, on the one
hand, the contact region wears after a period of use and so the lower sash
is no longer securely held and, on the other hand, that a two-handed
operation of the locking mechanism is required.
A major disadvantage with sash type windows is the difficulty in obtaining
a satisfactory seal between the frames of the sashes themselves and the
window frame when the window is in its closed position. Such a seal is
important to prevent draughts. Thus, it is an object of the present
invention to provide a locking mechanism for sash windows in which a
better seal is obtained when the window is in its closed position, and
which can be operated with one hand.
SUMMARY OF THE INVENTION
This object is attained by a locking mechanism of the type identified in
the introduction of the description in which the locking mechanism is
operable by a handle which, when the locking mechanism is in a locked mode
and the sashes are in the closed position, causes at least one sash clamp
to engage a cooperating receiving element affixed to the adjacent rail of
the other sash, and further effects the contact of a locking bolt at
either end of the transverse rail against side walls of a window sash
guide groove in a window frame enclosing said upper and lower sashes and
which handle, when the locking mechanism is in an open mode, causes the
locking bolts to release the contact with the groove's side walls, whilst
still remaining within the groove and further causes the sash clamp to
disengage from its receiving element.
In a preferred embodiment of the invention, the contacting surfaces of the
sash clamp and its corresponding receiving element are so shaped that,
upon engagement of the sash clamp with the receiving element, the upper
transverse rail of the lower window sash is drawn towards the adjacent
rail of the other sash. This effects a better seal between the said rails
of the window sashes.
Similarly, in another embodiment the contacting surfaces of the sash clamp
and its corresponding receiving element are so shaped that, upon
engagement of the sash clamp with the receiving element, the upper sash is
vertically upwardly displaced with respect to the lower sash. Such
displacement ensures a better seal between the sash frames and the window
frame.
The movement of the locking bolts between the open and locked mode may be
effected by a cam element for each locking bolt causing rotation of the
locking bolts about a respective pivot point within the locking mechanism.
Advantageously, each cam element is operated via a connecting rod to which
said sash clamp is attached for movement between the open and locked
position.
Preferably, the movement of the handle is transmitted to the cam elements
and sash clamp via respective sash clamp actuator rods connected to
respective flanges on a first disk rotated by said handle.
The locking mechanism according to the invention may also be provided with
a third operating mode in which the locking bolts are fully retracted from
the guide groove to permit the lower sash to be moved in a non-vertical
plane. Thus, the lower sash can be swung inwardly to allow easier access
for cleaning of the sash.
Advantageously, said retraction of the locking bolts is effected by
respective lock pin actuator rods connected to respective flanges on a
second disk rotated by said handle.
In a preferred embodiment said first and second disks are arranged for
independent rotation about a spindle of said handle, each disk being
provided with a shaped opening for the accommodation of a correspondingly
shaped spigot formed on said spindle. Preferably, when the locking
mechanism is in its locked mode, these openings in the disks are offset by
a certain angle whilst, in the open mode, these openings are aligned.
In order to switch from the open mode to the third mode, the spigot on the
spindle of the handle may be displaced along the axis of the spindle so
that the spigot engages with said second disk, said handle then being
rotated to cause the retraction of the locking bolts via the respective
locking bolt actuator rods.
In a further preferred embodiment the lower sash can be locked in any open
position by causing said locking bolts to contact said side surface of the
window frame groove by rotation of said handle to switch the locking
mechanism from the open mode to the locked mode.
The present invention will be more fully described in the following by way
of example only with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic perspective view of a sash window assembly provided
with a locking mechanism according to the present invention;
FIG. 2 is a partially sectioned view of the locking mechanism in its
mounted state on the upper transverse rail of the lower window sash;
FIG. 2a is a plan view and cross section of an upper disk in the locking
mechanism;
FIG. 2b is a plan view and cross section of a lower disk in the locking
mechanism;
FIG. 3 is a plan view of the locking mechanism without its top cover and in
its locked mode;
FIG. 3a is a plan view of a part of the locking mechanism in engagement
with the adjacent sash;
FIG. 3b is a section along line B--B of FIG. 3a;
FIG. 4 is a plan view similar to FIG. 3, but with the locking mechanism in
its open mode;
FIG. 5 is a plan view of the locking mechanism in its third mode.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
Referring to FIG. 1, the upper and lower sliding sashes of a window
assembly are indicated by the reference numerals 1 and 2 respectively,
each sash being enclosed by a frame composed of side rails 3,3 and
transverse rails 4,4, the top and bottom transverse rails of the lower and
upper sashes respectively forming the meeting rail of the respective sash
which, when the sashes are in the closed position, abuts the adjacent rail
on the other sash, as best seen in FIG. 3b.
The locking mechanism according to the present invention is attached to the
top surface of the transverse rail 4 of the lower sash 2. The mechanism is
housed in a substantially rectangular casing 5 and is operated by a handle
6. In the drawings the handle is shown centrally mounted on the mechanism,
with the mechanism being symmetric about the centre line of the handle.
For reasons of simplicity, only one half of the mechanism is shown in the
remaining drawings. However, it is to be understood that the handle need
not to be centrally mounted but may be offset if circumstances so dictate.
The handle arrangement is best shown in FIG. 2. A spindle 7 extends from
the handle 6 into the casing 5 of the locking mechanism. A spigot 8 is
provided at the end of the spindle 7 remote from the handle. The spigot 8
cooperates with either one of two adjacent disks 9,10 arranged for
independent rotation with the spindle 7. The lower disk 9 has a recess or
opening 11 to accommodate the spigot 8 and is rotatably supported in a
handle housing 13 within the casing 5, whilst the upper disk 10 has a
through-opening 12 to accommodate the spigot 8 and is rotatably supported
by the lower disk 9. Each disk is slightly thicker than the height of the
spigot 8.
Each disk has the same circumferential form, i.e. substantially circular
with two diametrically opposed, radially outwardly extending flanges 14.
When the disks 9,10 are superimposed, their openings 11,12 are offset by
90.degree..
A vertical pin 15 is formed on each flange 14 on the line of symmetry
bisecting the disks 9,10. These pins cooperate with elements of the
locking mechanism for controlling the respective functions of the
mechanism as described in the following.
The locking mechanism has three modes of operation, i.e. a locked mode, an
open mode and a "cleaning" mode respectively.
With reference to FIGS. 3, 3a and 3b, two sash clamps 16 are provided, one
on either side of the handle arrangement. Since the locking mechanism is
symmetric about the handle arrangement, only the left-hand half of the
mechanism as shown in the drawings will be described in the following. In
the shown locked position, the sash clamp 16 firmly engages a receiving
element 17 mounted on the top surface of the lower transverse rail 4 of
the upper sash 1.
As best shown in FIG. 3a, the contacting surfaces of the sash clamp and
receiving element are so shaped that, upon engagement of the sash clamp
with the receiving element, the upper transverse rail of the lower window
sash is drawn towards the adjacent rail of the other sash.
As best shown in FIG. 3b, the upper contacting surface of the sash clamp
and the respective surface of the receiving element are so shaped that,
upon engagement of the sash clamps with the receiving element, the upper
sash is slightly vertically displaced with respect to the lower sash.
Seen from above, the sash clamp 16 is dog-leg shaped and is made to pivot
about a vertical pivot pin 18 passing through the mid point of the
dog-leg. The pivot pin 18 is attached at its lower end to the base of the
casing 5, whilst its upper end is located in a horizontally disposed pivot
pin locating plate 19 within the casing 5.
Sash clamp 16 is pivotably attached to a connecting rod 20 which extends in
a horizontal plane parallel to the casing 5. One end of the connecting rod
20 is connected to a cam element whilst its other end is connected via a
pivot link 22 to one end of a sash clamp actuator rod 23. The other end of
the sash clamp actuator rod 23 is pivotably attached to the vertical pin
formed on the flange 14 of the lower disk 9.
An actuator rod 24 is similarly connected to the vertical pin of the upper
disk 10. This rod 24 extends horizontally and terminates with a pivot link
25. Connected to this pivot link is a locking bolt 26.
In the locked mode as shown in FIG. 3, the lower and upper disks 9,10 are
so arranged that the vertical pins 15 on the flanges 14 lie on a common
vertical axis, equidistant from the vertical side walls of the casing 5.
Both the cam element 21 and the locking bolt 26 are supported by a guide
block 27 at the extreme end of the locking mechanism cover. Locking bolt
26, via a through-passage 28, passes through said guide block 27 and
protrudes into a groove 33 in the vertical elements 34 of the window frame
enclosing the two sash windows. For reasons of clarity, the groove and
vertical element shown in the drawings are merely schematic
representations on a larger scale than the rest of the locking mechanism.
In actual practice, the clearences around the locking bolt are very much
smaller than shown. To reduce wear, the groove may be provided with some
form of lining. The through-passage 28 is so shaped that the locking bolt
26 is allowed to rotate through several degrees about the pivot link 25 on
the actuator rod 24. This pivotal movement is resisted by a spring member
29 in the through-passage 28.
In the locked position as shown in FIG. 3, the locking bolt 26 is forced
against the spring member 29 into a position where the bolt 26 engages the
side wall 35 of the groove in the vertical element of the window frame.
The reaction between the locking bolt 26 and the groove side wall 35
pushes the lower sash 2 towards the upper sash 1, thereby effecting a
better seal between the transverse rails 4,4 of these sashes.
Locking bolt 26 is forced into its locked position by means of the cam
element 21 acting on a roller or ball-bearing 30 located in the guide
block 27 in a connecting passage between the locking bolt through-passage
28 and a through-passage 31 for the cam element 21. The position of the
cam element is controlled by the sash clamp actuator rod 23. Thus, when
the sash clamp 16 is in its outwardly extended (e.g. locked) position, the
cam element 21 acts on the roller 30 to force the locking bolt 26 into its
locked position. Since the sash clamp 16 and the locking bolt 26 are
operated substantially simultaneously via the handle 6, a more even
distribution of forces around the sash frame when the mechanism is in its
locked mode is achieved.
In the locked mode, the spigot 8 on the spindle 7 of handle 6 rests in the
opening 11 of the lower disk 9. To move the locking mechanism to its open
position, handle 6 is turned through 90.degree. to the position shown in
FIG. 4.
The displacement of the handle 6 is transmitted via the spindle 7 and
spigot 8 to lower disk 9. After 90.degree. of rotation, the disk's
movement is blocked by stop pins 32 mounted in the handle-housing 13
abutting the flanges 14 on the disk. As shown in the figures, sash clamp
actuator rod 23 is thereby drawn to the right and sash clamp 16 is rotated
through 90.degree. to disengage from its receiving elements 17 due to
displacement of the connecting rod 20.
The attachment between the connecting rod 20 and the cam element 21 is such
that the connecting rod 20 is allowed independent movement for the first
part of its travel, with the cam element being engaged only for the latter
movement. This latter movement withdraws cam element 21 to a position
whereat the roller or ball-bearing 30 can partially project into the
through-passage 31 of the cam element 21. Due to the action of the spring
member 29 on the locking bolt 26, in this position the locking bolt 26
lies between the side walls of the grooves in the window frame, thereby no
longer hindering movement of the lower sash 2 with respect to the window
frame. Thus, the lower sash 2 may now be raised to open the window.
The lower sash 2 can be held in any desired open position by turning the
handle 6 back to its locked position. Hereby the cam element 21 forces the
locking bolt 26 against the action of the spring member 29 into its locked
position against the side wall of the window frame groove. Naturally, the
sash clamp 16 will also be moved to its locked position, though since the
receiving element 17 does not move with the lower sash 2, the sash clamp
16 merely projects towards the upper sash 1.
Should the displacement of the lower sash 2 wish to be restricted, e.g. to
allow a gap which is too small for children to climb through, releasable
blocking pieces can be inserted into the window frame grooves at the
appropriate height to prevent the lower sash 2 passing these blocking
pieces.
The final mode of operation of the locking mechanism is the so-called
cleaning mode. In this mode, the lower sash 2 can be swung away from the
window frame to allow its outer surface to be cleaned from the inside.
This mode is shown in FIG. 5.
When the window is closed, e.g. when sash clamp 16 is cooperable with its
receiving element 17, and the locking mechanism is in its open mode, the
handle 6 is lifted so that spigot 8 passes from the lower disk 9 into the
through-opening 12 of the upper disk 10. The handle 6 is then turned
through 90.degree., effecting rotation of the upper disk 10, but not the
lower disk 9. Lock pin actuator rod 24 is hereby moved to the right as
shown in the figures, thereby drawing the locking bolt 26 fully into the
guide block 27. Since there is no part of the lock mechanism or the lower
sash 2 which now projects into the window frame groove, the lower sash is
no longer restricted to movement solely in a vertical plane. By means of a
not shown hinge arrangement, the lower sash may be pivoted about the
transverse rail 4 of the upper sash 1.
It is to be understood that the present invention is not restricted to the
above-described embodiment, but may be varied within the scope of the
appended claims. For example, the sash clamps may be more or less than two
in number. Similarly, pairs of sash clamps may be provided with one sash
clamp arranged above the other, with the surfaces of the clamps facing
away from each other cooperating with surfaces of a receiving element to
effectively double the clamping force between the two sashes. Furthermore,
the different modes of the locking mechanism need not be operable by
90.degree. stepwise displacement of the handle; other angles may be chosen
provided that the through-openings of the disks coincide in the open mode.
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